Grain grinding mill with adjustable nonrotary member



g- 12, 1952 A. B. GRONBERG 2,606,722

GRAIN GRINDING MILL WITH ADJUSTABLE NONROTARY MEMBER Filed Nov. 22, .1948

INVENTOR.

ATTORNEYS.

Patented Aug. 12, 1952 UNITED STATES PATENT '()Flfl(3E w 2,606,722 I .r

GRAIN Gamma MILL WITH ADJUSTABLE j j NONROTARY MEMBER Anton Bertil Griinberg, Ottum, Sweden Application November 22, 1948, Serial No. 61,443 In Sweden December 5, 1947 1 Claim. 1

The present invention relates to grain grinding mills of the kind comprising two cylindrical, coaxial grinding stones mounted within a casing, oneof said stones (the runner) being fastened to a rotary horizontal shaft passing through the casing, while the other (a non-rotatable stone), which is axially movable for adjustment to and from the runner, is suspended and adjusted by a number of slidable rods passing through one wall of the casing. In this kind of mill an adjustable tightening device is adapted to press the non-rotatable grinding stone against the runner by means of the said rods.

The invention is broadly characterized in that the tightening device is connected to the one end of the shaft carrying the runner by means of a coupling, so that the reaction stress occurring on the tightening device when the nonrotatable grinding stone is forced against the runner will be taken up by said shaft. Such a device avoids imposing this reaction stress on the mill casing, which is very advantageous particularly in cases where the mill casing is made wholly or mainly from wood.

An embodiment of the invention is shown in the accompanying drawing, in which Figure 1 is a horizontal section through a mill according to the invention, While Figure 2 is a side View partly in section of the mill.

In the drawing I and 2 denote the wooden side walls of the cylindrical casing and 3 its mantle. In bearings 6 and I carried by a wooden stand 8 there is rotatably and axially slidably mounted a shaft 5 passing horizontally through the casing and carrying near one end a driving pulley i. Within the casing and adjacent one of the side walls (I) there is provided a cylindrical grinding stone 9 (the runner) which is fixed on the shaft 5 so as to be driven thereby, and adjacent the opposite side wall 2 there is provided a nonrotatable cylindrical grinding stone Ill, which during operation is stationary. 'The stone I has a central opening through which the material to be ground (the grain) is fed from a container I l to the space between the grinding stones by means of a feeding screw (not shown) mounted on the shaft in a known manner. The stone I0 is surrounded by an iron band I2 to which a pin 13 is fixed. Said pin passes through an axial slot 14 at the top of the mantle 3 and is at its upper end formed with an enlarged head l5, which by resting upon the portions of the mantle 3 adjacent the slot l4 carries the stone ID.

At each side of the shaft 5 and horizontally level with the same there are provided two rods 15b, parallel with the shaft 5, and these pass slidably through openings [5a in the side wall 2 with their inner ends abutting against the stone Ill. The outer ends of these slidable rods lEb are screw-threaded and are adjustably connected to the ends of a yoke 18. In the middle portion of said yoke 16 there is provided an opening ll into which is inserted an internally screwthreaded sleeve l9 which is tiltably mounted on two trunnion pins l8 provided opposite each other. Through said sleeve [9 passes a screwthreaded operating spindle 20, which is co-axial with the shaft 5 and provided with a hand-wheel 21. To the end of the shaft 5 facing the yoke it there is fastened by means of a cross-pin one end of a sleeve 22, and through the other end of said sleeve 32, which is formed with an inwardly projecting flange 23, there is introduced an end portion 24 of the screw spindle 2B. To the free end of said end portion 24 there is fastened a ring 25, and between this and the end flange 23 of the sleeve 22 there is provided a ball bearing 25, the whole constituting a coupling between the spindle 20 and shaft 5 which allows relative rotation between these two members. Between the sleeve l9 and the hand-wheel 2| there is mounted on the screw spindle 28 a locking nut 28 with a projecting handle 21.

The grinding stone I0 is forced towards the runner stone 9 by rotating the screw spindle 20 by means of the hand-wheel 2|, which causes the sleeve 19 with the yoke IE to be moved in a direction towards the stone til, it is clear that the reaction stress occurring on the screw spindie 2?) will be taken up by the shaft 5 carrying the runner 9, through the medium of the bearing 25. r

The invention is not limited to the embodiment described above and shown in the accompanying drawing, but may be varied in details without departing from the spirit of it.

What I claim is:

An improvement in grain grinding mills comprising a casing, a pair of coaxial grinding stones positioned within said casing, a driving shaft rotatably mounted and extending through said casing and said stones with one of said stones affixed thereto for rotation therewith, said cas ing having a slot formed in the top thereof extending parallel to said shaft, a pin slidably mounted on said casing and extending through said slot with the other of said stones suspended therefrom, a pair of rods slidably mounted each on an opposite side of said shaft through said casing and bearing against said second stone for axially moving the same towards said rotatable stone, a. yoke connected to said rods, an operating spindle having screw threads formed thereon, an interiorly threaded sleeve carriedby said yoke and having said spindle extending therethrough in threaded engagement therewith and coupling means rotatably supporting said spindle on said shaft and axially transmitting the thrustof said spindle to said shaft. 1 A

ANTON BERTIL GRONBERG.

REFERENCES CITED Number 10 Number UNITED STATES PATENTS Name Date Foreman Sept. 13, 1870 Wagner Feb. 4, 1879 Raymond Dec. 7, 1886 McLaughlin Feb. 6, 1906 FOREIGN PATENTS Country Date Germany Mar. 8, 1880 Germany Dec. 14, 1892 Germany July 6, 1915 

